Select the corresponding metalworking fluid for different cutting tools

Tool steel

Its heat resistance temperature is between 200~300 °C, it can only be used for cutting of general materials, and it will lose hardness at high temperature. Due to the poor heat resistance of the tool, the cooling effect of the coolant is required to be good, and an emulsion is generally preferred.

High speed steel

This material is a high-grade alloy steel based on chromium, nickel, tungsten, molybdenum, vanadium (some also containing aluminum), which is significantly more heat resistant than tool steel and allows a maximum temperature of up to 600 °C. Compared with other high temperature resistant metal and ceramic materials, high speed steel has a number of advantages, especially its high toughness, suitable for geometrically complex workpieces and continuous cutting, and high speed steel has good workability and The price is easy to accept. Oil-based cutting fluids or emulsions are recommended for low-speed and medium-speed cutting with high-speed steel tools. In high-speed cutting, it is preferable to use a water-based cutting fluid because of the large amount of heat generation. If oil-based cutting fluid is used, it will produce more oil mist, pollute the environment, and it will easily cause burns on the workpiece, the processing quality will decrease, and the tool wear will increase.

Cemented carbide

The cemented carbide used in cutting tools is composed of tungsten carbide (WC), titanium carbide (TiC), tantalum carbide (TaC) and 5-10% cobalt. Its hardness greatly exceeds that of high speed steel, and the maximum allowable working temperature is up to 1000 ° C, with excellent wear resistance, can reduce the bond between the chips when processing steel materials. When selecting the cutting fluid, consider the sensitivity of the cemented carbide to the sudden heat, and make the tool evenly heated as much as possible, otherwise it will cause chipping. In the processing of general materials, dry cutting is often used, but in dry cutting, the temperature rise of the workpiece is high, the workpiece is prone to thermal deformation, affecting the machining accuracy of the workpiece, and cutting without lubricant, due to cutting resistance Larger, the power consumption is increased, and the wear of the tool is also accelerated. Carbide tools are more expensive, so from an economic point of view, dry cutting is not cost effective. When the cutting fluid is selected, the heat transfer performance of the oil-based cutting fluid is generally poor, and the risk of quenching the tool is smaller than that of the water-based cutting fluid. Therefore, it is generally preferred to use an oil-based cutting fluid containing an anti-wear additive. When cutting with a coolant, be careful to evenly cool the tool. It is best to cool the tool with cutting fluid before starting the cutting. For high-speed cutting, it is necessary to spray the cutting zone with a large flow of cutting fluid to avoid chipping caused by uneven heating of the tool, and to reduce the soot pollution caused by evaporation caused by excessive temperature.

ceramics

It is made of alumina, metal and carbide sintered at high temperature. The high temperature wear resistance of this material is better than that of hard alloy. Dry cutting is generally used, but it is often used in consideration of uniform cooling and avoiding excessive temperature. Water based cutting fluid.

Diamond

It has extremely high hardness and is generally used for cutting. To avoid excessive temperatures, as with ceramic materials, water-based cutting fluids are used in many cases.